Developing apparatus for developing exposed films



ly 1967 M. BCEGER ETAL DEVELOPING APPARATUS FOR DEVELOPING EXPOSED FILMS Filed Jan. 18, 1965 C .5 U R .L w/ fl m m H N A K E J \L V d V f A m M v 4 mr 7 M. WTJH H H H I w y m I United States Patent Ofifice 3,330,197 Patented July 11, 1967 DEVELOPING APPARATUS FOR DEVELOPING EXPOSED FILMS Marius Biieger, Gut Stend'orf uber Eutin, Germany, and Alfred Krueger, Fruchtallee 109, Hamburg, Germany Filed Jan. 18, 1965, Ser. No. 426,165

Claims priority, application Germany, Jan. 18, 1964,

6 Claims. (CI. 95-94) ABSTRACT OF THE DISCLOSURE A developing apparatus in which adeveloping liquid is applied to the emulsion side of an exposed film by a pair of superimposed rolls the lower one of which dips into a developing liquid, in which the film is subsequently guided by guide means through a fixing liquid and in which a pair of fixing rolls arranged between the firstnentioned pair of rolls and the guide means cooperate with the fixing liquid and the film for applying the fixing liquid to the emulsion side thereof so as to abruptly stop further developing of the film.

The present invention relates to a two bath developing apparatus for developing exposed elongated films. Such developing apparatus is known in the art and it usually comprises a developing bath and a fixing bath downstream of the developing bath, at least one pair of superimposed rolls for feeding the elongated exposed film from the developing bath into the fixing bath, and guide elements which guide the film in a curve through the fixing bath to a pair of squeeze rolls at the end or above the fixing bath.

In developing apparatus of this type according to the prior art, it is known to arrange the leading ends of an upper and a lower guide element closely adjacent to the gap between the rolls which feed the film from the developing bath into the fixing bath. This has however the disadvantage that droplets from the liquid forming the developing bath will be deposited from the moist film onto the leading end of the lower guide element projecting beyond the fixing bath so that the following film portion passing over this leading end of the lower guide element to which the droplets from the developing bath will adhere, will be subjected to an additional developing action causing thereby a diiferent shading value in part of the film. To avoid this ditficulty, it is known to shorten the lower guide element in such a manner that it does not project above the fixing bath. This, however, has the disadvantage that the trailing end of the film, after having passed through the gap between the rolls cooperating with the developing bath, will drop downwardly and engage a portion of the cylindrical surface of the lower one of these rolls rearwardly of the gap. This will likewise lead to an additional moistening of the end of the film and therefore to a greater developing of this film end as compared to the remainder of the film. Furthermore, in such an arrangement the trailing end portion of the film will, after it has passed through the pair of developing rolls, suddenly impinge on the liquid in the fixing bath. This will result that the end portion of the film will be subjected to a shorter action of the developing liquid than the remainder of the film, which in turn will result in different density value in the film end portion. Another disadvantage of developing apparatus of this type known in art is that the leading edge of the film, after leaving the fixing bath, may butt against one of the squeeze rolls before being received in the nip between the pair of squeeze rolls. This may result in an upsetting of the film which may be carried up to the developing rolls and cause the film downstream of the developing rolls to bend upwardly so that the thus upwardly bent film portion will be subjected to a longer developing action than the remainder of the film, which in turn will lead also to a difierent density value in the aforementioned overdeveloped portion of the film.

It is an object of the present invention to overcome these disadvantages of a two bath developing apparatus.

It is a further object of the present invention to provide a two bath developing apparatus in which all portions of the film passing therethrough will be subjected to the same developing action so that undesired over developing of certain portions of the film while the same is passed through the apparatus is positively avoided.

It is an additional object of the present invention to provide a developing apparatus which is composed of only a few and relatively simple parts so that the apparatus can be manufactured at reasonable cost and will operate trouble free during an extended time period.

With these objects in view, the developing apparatus of the present invention mainly comprises a first tank adapted to contain a developing liquid, a second tank arranged adjacent the first tank and adapted to contain a fixing liquid, and means for successively applying the developing liquid and the fixing liquid to the emulsion surface of an exposed photographic film and for feeding the film in one direction. The aforementioned means include according to the present invention at least one pair of superimposed rolls adapted to grip the film between the peripheral surfaces thereof and cooperating with the liquid in the first tank for applying the liquid to the emulsion surface of the film and for transporting the film from the first to the second tank, guide means in the second tank for guiding the film through th e fixing liquid therein, a second pair of superimposed rolls between the first mentioned pair of rolls and the guide means and adapted to grip the film between the peripheral surface thereof, in which the lower one of the second pair of superimposed rolls is arranged to dip into the fixing liquid, and a pair of squeeze rolls downstream of the guide means and arranged above the liquid in the second tank, and means operatively connected to the rolls for driving the same.

In this arrangement, the second pair of superimposed rolls, hereinafter also called fixing rolls, will grip the leading end of the film leaving the gap between the pair of rolls cooperating with the developing liquid in the first tank and guide the same toward the guide means, whereby the lower roll of the pair of fixing rolls, which dips into the fixing liquid in the second tank, will moisten the lower or emulsion side of the film with the fixing liquid. This moistening of the emulsion side of the film with the fixing liquid will abruptly interrupt any further developing action. This will assure that all portions of the film will be subjected to the same developing action and undesired after overdeveloping will be positively avoided.

To positively assure that the trailing end of the film, after leaving the pair of rolls cooperating with the developing liquid in the first tank, will not engage the upper edge of the first tank or the upper edge of the second tank adjacent thereto, it is preferred to arrange the upper one of the pair of fixing rolls in a position displaced towards the center of the second tank relative to the lower one of the pair of fixing rolls.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accom- 3 panying drawing, in which the figure is a schematic, longitudinal section through the developing apparatus according to the present invention.

Referring now to the drawing, it will be seen that the developing apparatus according to the present invention includes a first tank 1 adapted to contain a developing liquid 1' and forming a developing bath, and a second tank 2 closely adjacent to the first tank and adapted to contain a fixing liquid and forming a fixing bath. The tanks 1 and 2 are preferably of rectangular configuration and are open at their upper ends and they are preferably mounted on a common support plate 22 having an upwardly extending rim portion 2-2 preventing shifting of the tanks mounted thereon relative to the base plate 22. The apparatus includes further means for successively applying the developing liquid 1 in the first tank and the fixing liquid 2 in the second tank to the emulsion side e of an exposed photographic film F and for feeding the film in one direction. These means include at least one, and preferably, as shown in the drawing, two pairs of superimposed rolls 3 and 4 arranged spaced from each other in feeding direction in the region of the first tank, the two pairs of rolls 3 and 4 are respectively adapted to grip between peripheral surfaces thereof the film F and to feed the film during rotation of the rolls in the feeding direction as indicated by the arrow A. Each pair of rolls 3 and 4 has a lower roll dipping in the developing liquid 1 in the first tank 1 so as to apply during rotation thereof developing liquid to the emulsion side e of the film F engaging the peripheral surface of the lower ones of the pairs of rolls 3 and 4.

After the leading end of the film F leaves the pair of rolls 4, it will enter between the gap of a pair of fixing rolls 5 arranged at the front end of the second tank 2 as closely as possible to the pair of rolls 4. The lower one of the pair of fixing rolls 5 dips into the fixing liquid 2' in the second tank 2 so that the emulsion side e of the film F will be moistened with fixing liquid as soon as the film enters between the pair of fixing rolls 5, which will terminate the after developing of the film occurring while the film passes from the pair of rolls 4 to the fixing rolls 5.

The film leaving the pair of fixing rolls 5 is guided between a pair of superimposed curved guide elements 6 and 7, arranged spaced from each other in a direction transverse to the feeding direction downstream of the pair of fixing rolls 5, which guide the film F in a curve through the fixing liquid 2 in the tank 2 and which direct the leading end of the film into the nip of a pair of squeeze rolls 8 arranged downstream of the trailing end of the guide means 6 and 7 above the fixing liquid 2' in the second tank 2.

The two guide elements 6 and 7 of the guide means may be constituted by curved perforated plates or by two pairs of elongated curved strips respectively adapted to engage the outer edges of the film. The guide elements 6 and 7 may be attached to the side walls of the second tank in any known manner.

The aforementioned rolls are preferably made from elastic material such as rubber or the like and the lower ones of the pair of rolls 3, 4 and 5 are mounted on shafts which in turn may be turnably mounted in appropriate bearings, not shown in the drawing, connected to the side walls of the tanks 1 and 2. The upper ones of the pair of rolls 3, 4 and 5 and the pair of squeeze rolls 8 are likewise mounted on shafts having parallel axes and these shafts are mounted for rotation about their axes in bearings, also not shown in the drawing, which are supported on spaced parallel walls 23, one of which is shown in the drawing, extending upwardly from the base plate 22. The shafts project with an end portion thereof beyond the outer surface of the wall 23 shown in the drawing and the end portions of the shafts respectively carry gears 13, 14,- and 16 fixed to the respective shaft for rotation therewith. A gear 17 is located between the gears 13 and 14 and in meshing relationship therewith. Gear 17 is fixedly mounted on a shaft 29 which in turn is driven by means of a reduction gear means 21 from a motor, not shown in the drawing. An idler gear 18 is located between the gears 14 and 15 in meshing relationship with the latter and this idler gear may be turnably mounted on a stud shaft fixed to the wall 23 and projecting to the outer side thereof. An additional idler gear 19 is located between the gears 15 and 16 and in meshing relationship therewith and the idler gear 19 is likewise turnably mounted on a stud shaft carried by the wall 23. The gears 13, 14, 15 and 16 have the same pitch diameter and the same number of teeth and the gears 17, 18 and 19 also have identical pitch diameters and identical number of teeth so that the driven rolls of the pair of rolls 3, 4, 5 and 8 which all have the same diameter are driven with identical circumferential speeds.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of developing apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in a developing apparatus having two tanks respectively containing a developing liquid and fixing liquid, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a developing apparatus, in combination, a first tank adapted to contain a developing liquid; a second tank arranged adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including at least one pair of superimposed rolls adapted to grip the film between the peripheral surfaces thereof and cooperating with the liquid in said first tank for applying said liquid to the emulsion side of said film and for transporting the film from said first to said second tank, guide means in said second tank for guiding the film through the fixing liquid therein, a second pair of superimposed rolls between said first mentioned pair of rolls and said guide means and adapted to grip the film between the peripheral surfaces thereof, said first and said second pair of rolls being arranged close to each other and in such a manner that the film is guided between said pairs of rolls along a short substantially straight path, the lower one of said second pair of superimposed rolls engaging the emulsion side of the film and adapted to dip into the fixing liquid so as to apply fixing liquid to the emulsion side as the film passes between said second pair of rolls, a pair of squeeze rolls downstream of said guide means and both arranged above the liquid in said second tank, and means operatively connected to said rolls for driving the same.

2. In a developing apparatus, in combination, a first tank adapted to contain a developing liquid; a second tank arranged adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including at least one pair of superimposed rolls adapted to grip the film between the peripheral surfaces thereof and cooperating with the liquid in said first tank for applying said liquid to the emulsion side of said film and for transporting the film from said first to said second tank, a pair of curved guide means arranged spaced from each other in direction transverse to said feeding direction located in said second tank for guiding the film through the fixing liquid therein, a second pair of superimposed rolls between said first mentioned pair of rolls and said guide means and adapted to grip the film between the peripheral surfaces thereof, said first and said second pair of rolls being arranged close to each other and in such a manner that the film is guided between said pairs of rolls along a short substantially straight path, the lower one of said second pair of superimposed rolls engaging the emulsion side of the film and adapted to dip into the fixing liquid so as to apply fixing liquid to the emulsion side as the film passes between said second pair of rolls, a pair of squeeze rolls downstream of said guide means and both arranged above the liquid in said second tank, and means operatively connected to said rolls for driving the same.

3. In a developing apparatus, in combination, a first tank adapted to contain a developing liquid; a second tank arranged adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including at least one pair of superimposed rolls adapted to grip the film between the peripheral surfaces thereof and cooperating with the liquid in said first tank for applying said liquid to the emulsion side of said film and for transporting the film from said first to said second tank, a pair of curved guide means arranged spaced from each other in direction transverse to said feeding direction located in said second tank for guiding the film through the fixing liquid therein, a second pair of superimposed rolls between said first mentioned pair of rolls and said guide means and adapted to grip the film between the peripheral surfaces thereof, said first and said second pair of rolls being arranged close to each other and in such a manner that the film is guided between said pairs of rolls along a short substantially straight path, the lower one of said second pair of superimposed rolls engaging the emulsion side of the film and adapted to dip into the fixing liquid so as to apply fixing liquid to the emulsion side as the film passes between said second pair of rolls, the upper one of said second pair of rolls being displaced relative to the lower one towards the center of said second tank, a pair of squeeze rolls downstream of said guide means and both arranged above the liquid in said second tank, and means operatively connected to said rolls for driving the same.

4. A developing apparatus comprising, in combination, support means; a first substantially rectangular tank having an open top mounted on said support means and adapted to contain a developing liquid; a second substantially rectangular tank having an open top mounted on said support means closely adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including two pairs of superimposed rolls arranged spaced from each other in feeding direction in the region of said first tank, said two pairs of rolls respectively adapted to grip between peripheral surfaces thereof the film and each pair having a lower roll adapted to dip in the developing liquid in said first tank so as to apply during rotation thereof developing liquid to the emulsion side of a film engaging the peripheral surface of the lower ones of said rolls, a pair of superimposed fixing rolls in the region of said second tank adjacent said first tank and adapted to grip the film between the peripheral surfaces thereof,

the one pair of rolls in said first tank which follows in feeding direction the other of said two pairs is arranged closely adjacent said pair of fixing rolls and in such a manner that the film is guided between said one pair of rolls and said fixing rolls along a short substantially straight path, the lower one of said pair of superimposed fixing rolls adapted to dip into the fixing liquid in said second tank to apply said fixing liquid to the emulsion side of the film as the latter moves from said first to said second tank, curved guide means in said second tank downstream of said pair of fixing rolls for guiding the film through the fixing liquid in said second tank, a pair of squeeze rolls downstream of said guide means and arranged above the liquid in said second tank, and means operatively connected to said rolls for driving the same.

5. A developing apparatus comprising, in combination, support means; a first substantially rectangular tank having an open top mounted on said support means and adapted to contain a developing liquid; a second substantially rectangular tank having an open top mounted on said support means closely adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including two pairs of superimposed rolls arranged spaced from each other in feeding direction in the region of said first tank, said two pairs of rolls respectively adapted to grip between peripheral surfaces thereof the film and each pair having a lower roll adapted to dip in the developing liquid in said first tank so as to apply during rotation thereof developing liquid to the emulsion side of a film engaging the peripheral surface of the lower ones of said rolls, a pair of superimposed fixing rolls in the region of said second tank adjacent said first tank and adapted to grip the film between the peripheral surfaces thereof, the one pair of rolls in said first tank which follows in feeding direction the other of said two pairs is arranged closely adjacent said pair of fixing rolls and in such a manner that the film is guided between said one pair of rolls and said fixing rolls along a short substantially straight path, the lower one of said pair of superimposed fixing rolls adapted to dip into the fixing liquid in said second tank to apply said fixing liquid to the emulsion side of the film as the latter moves from said first to said second tank, curved guide means in said second tank downstream of said pair of fixing rolls for guiding the film through the fixing liquid in said second tank, a pair of squeeze rolls downstream of said guide means and arranged above the liquid in said second tank, the upper one of said pair of fixing rolls being displaced relative to the lower one towards the center of said second tank and one roll of said pair of squeeze rolls being closer to said upper one of said pair of fixing rolls than the other of said squeeze rolls, and means operatively connected to said rolls for driving the same.

6. A developing apparatus comprising, in combination, support means; a first substantially rectangular tank having an open top mounted on said support means and adapted to contain a developing liquid; a second substantially rectangular tank having an open top mounted on said support means closely adjacent said first tank and adapted to contain a fixing liquid; and means for successively applying said developing liquid and said fixing liquid to the emulsion side of an exposed photographic film and for feeding said film in one direction, said means including two pairs of superimposed rolls arranged spaced from each other in feeding direction in the region of said first tank, said two pairs of rolls respectively adapted to grip between peripheral surfaces thereof the film and each pair having a lower roll adapted to dip in the developing liquid in said first tank so as to apply during rotation thereof developing liquid to the emulsion side of a film engaging the peripheral surface of the lower ones of said rolls, a pair of superimposed fixing rolls in the region of said second tank adjacent said first tank and adapted to grip the film between the peripheral surfaces thereof, the one pair of rolls in said first tank which follows in feeding direction the other of said two pairs is arranged closely adjacent said pair of fixing rolls and in such a manner that the film is guided between said one pair of rolls and said fixing rolls along a short substantially straight path, the lower one of said pair of superimposed fixing rolls adapted to dip into the fixing liquid in said second tank to apply said fixing liquid to the emulsion side of the film as the latter moves from said first to said second tank, curved guide means in said second tank downstream of said pair of fixing rolls for guiding the film through the fixing liquid in said second tank, a pair of squeeze rolls downstream of said guide means and arranged above the liquid in said second tank, the upper one of said pair of fixing rolls being displaced relative to the lower one towards the center of said second tank and one roll of said pair of squeeze rolls being closer to said upper one of said pair of fixing rolls than the other of said squeeze rolls, the upper one of each pair of rolls in said first tank, the upper one of said fixing rolls, and the one roll of said 3 squeeze rolls being respectively fixedly mounted on shafts having parallel axes and mounted for rotation on said support means, a first plurality of gears respectively mounted on said shafts for rotation therewith, a second plurality of gears turnably mounted on said support means and respectively located between said gears of said first plurality of gears and meshing therewith, and means operatively connected to one of said gears for driving the same.

References Cited UNITED STATES PATENTS 3,107,596 10/1963 Arnold et a1 9589 3,186,325 6/1965 De Belder 95-89 3,242,843 3/1966 Tillotson et al. 95-89 FOREIGN PATENTS 1,337,297 8/1963 France.

943,653 12/ 1963 Great Britain.

NORTON ANSHER, Primary Examiner.

FRED L. BRAUN, Assistant Examiner. 

1. IN A DEVELOPING APPARATUS, IN COMBINATION, A FIRST TANK ADATPED TO CONTAIN A DEVELOPING LIQUID; A SECOND TANK ARRANGE ADJACENT SAID FIRST TANK AND ADAPTED TO CONTAIN A FIXING LIQUID; AND MEANS FOR SUCCESSIVELY APPLYING SAID DEVELOPING LIQUID AND SAID FIXING LIQUID TO THE EMULSION SIDE OF AN EXPOSED PHOTOGRAPHIC FILM AND FOR FEEDING SAID FILM IN ONE DIRECTION, SAID MEANS INCLUDING AT LEAST ONE PAIR OF SUPERIMPOSED ROLLS ADAPTED TO GRIP THE FILM BETWEEN THE PERIPHERAL SURFACE THEREOF AND COOPERATING WITH THE LIQUID IN SAID FIRST TANK FOR APPLYING SAID LIQUID TO THE EMULSION SIDE OF SAID FILM AND FOR TRANSPORTING THE FILM FROM SAID FIRST TO SAID SECOND TANK, GUIDE MEANS IN SAID SECOND TANK FOR GUIDING THE FILM THROUGH THE FIXING LIQUID THEREIN, A SECOND PAIR OF SUPERIMPOSED ROLLS BETWEEN SAID FIRST MENTIONED PAIR OF ROLLS AND SAID GUIDE MEANS AND ADAPTED TO GRIP THE FILM BE- 